In the field of ink ribbons for printers, a ribbon supply spool and a ribbon take-up spool generally have been provided on opposite sides of a typing or printing station, together with means for reversing the direction of travel of the ribbon for repeated use thereof in an arrangement for the purpose of obtaining longer ribbon life. Also, the ink ribbon has been made to travel along a line of printing wherein the spools are positioned beyond the ends of the printing line and the ribbon is caused to travel at an angle relative to the print line to utilize a greater portion of the ribbon width. However, in the case of certain high-speed printers, a ribbon substantially as wide as the line of printing may be used and caused to travel in a direction normal to the print line and along with the record media. Additionally, it has been common to provide ink carrying or containing means operably associated with the ribbon for maintaining or replenishing a supply of ink therein for proper and extended-life printing operation.
In present-day printers, it is also common practice to provide and use a ribbon cassette carrying an endless ribbon which is caused to be driven past the printing station, and wherein the printing ribbon is either a pre-inked and disposable ribbon or a ribbon which is to be continuously or frequently reinked during the printing operation. The ribbon cassette itself may be of the stuffing-box type wherein the ribbon is contained within the cassette in random manner and such ribbon is unfolded at the cassette exit and caused to be driven past the printing station and then guided back into the cassette to be folded again in random manner therein.
Additionally, a ribbon may be utilized in a Mobius loop configuration within the cassette, it may be in substantially continuous contact with an inking core or like member, or the ribbon may have a plurality of coils thereof around a central core for controlled inking or reinking of the ribbon.
Furthermore, it is noted that the Mobius loop configuration enables uniform use of both sides of the ribbon and also the upper and lower portions of each side thereof to prolong ribbon life.
Representative documentation relating to ribbon cassettes or cartridges includes U.S. Pat. No. 4,130,367, issued to G. Guerrini et al. on Dec. 19, 1978, which discloses a cartridge having a Mobius loop section with guide elements of three ribs projecting alternately from a base and from a cover.
U.S. Pat. No. 4,227,820, issued to C. G. Falcetti on Oct. 14, 1980, discloses a cartridge wherein the ribbon is inverted to provide a Mobius loop by the use of two deflecting elements formed as a part of an arm and of the cover.
U.S. Pat. No. 4,279,522, issued to E. H. Yonkers on July 18, 1981, discloses a cartridge having a Mobius loop channel with the ribs extending upwardly from the base and a rib extending downwardly from the cover. The ribs are slanted and cause the ribbon to rotate about its axis during travel through the channel.
U.S. Pat. No. 4,293,234, issued to E. H. Yonkers et al. on Oct. 6, 1981, discloses a cartridge having a Mobius loop support molded integral with the cover and which includes a partition having downwardly converging end edges which serve to turn the ribbon.
U.S. Pat. No. 4,304,496, issued to M. P. Vidwans on Dec. 8, 1981, discloses a ribbon guide means having a front guide for vertical orientation of the ribbon, and upper and lower horizontal flanges for horizontal orientation of the ribbon to provide a 90.degree. twist, and then a further 90.degree. twist is effected between the flanges and a roller.
U.S. Pat. No. 4,383,774, issued to E. H. Yonkers on May 17, 1983, discloses a cartridge having a ribbon inverting device comprising a notch molded with the cover, a first ridge, a second ridge, a third ridge, and a fourth ridge to invert the ribbon 180.degree..
And, U.S. Pat. No. 4,493,572, issued to W. G. Van Ocker et al. on Jan. 15, 1985, discloses a long life inked-ribbon cassette with walls on the cover and a wall on a base to rotate the ribbon 180.degree..